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991.
Melissa Wasserstein Laila Arash-Kaps Antonio Barbato Renata Gallagher Roberto Giugliani Norberto Guelbert Carla Hollak Takayuki Ikezoe Robin Lachmann Olivier Lidove Paulina Mabe Eugen Mengel Maurizio Scarpa Ebubekir Senates Michel Tchan Jesus Villarrubia Yixin Chen Maria Iram Awan Monica Kumar 《Molecular genetics and metabolism》2021
992.
Paola Stefanelli Antonino Bella Giorgio Fedele Serena Pancheri Pasqualina Leone Paola Vacca Arianna Neri Anna Carannante Cecilia Fazio Eleonora Benedetti Stefano Fiore Concetta Fabiani Maurizio Simmaco Iolanda Santino Maria Grazia Zuccali Giancarlo Bizzarri Rosa Magnoni Pier Paolo Benetollo Antonio Ferro 《Clinical microbiology and infection》2021,27(4):633.e1-633.e7
ObjectivesA seroprevalence study of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was conducted in a high-incidence area located in northeastern Italy.MethodsAll citizens above 10 years of age resident in five municipalities of the Autonomous Province of Trento, with the highest incidence of coronavirus disease 2019 (COVID-19) cases, were invited to participate in the study. Among 6098 participants, 6075 sera and a standardized questionnaire administered face-to-face were collected between 5 May and 15 May 2020 and examined. Symptomatic individuals and their family contacts were tested by RT-PCR. Anti-SARS-CoV-2 antibodies were detected using an Abbott SARS-CoV-2 IgG assay, which was performed on the Abbott Architect i2000SR automated analyser. Seroprevalence was calculated as the proportion of positive results among the total number tested. A multivariable logistic regression model was performed to assess the relationship between seropositive versus seronegative individuals for a set of explanatory variables.ResultsA total of 1402 participants were positive for IgG antibodies against SARS-CoV-2, with a prevalence of 23.1% (1402/6075). The highest prevalence was found in the age class 40–49 years. Overall, 34.4% (2096/6098) of the participants reported at least one symptom. The ratio between reported cases identified by molecular test and those with seropositive results was 1:3, with a maximum ratio of about 1:7 in the age group <20 years and a minimum around 1:1 in those >70 years old. The infection fatality rate was 2.5% (35/1402). Among the symptoms, anosmia and ageusia were strongly associated with seropositivity.ConclusionsThe estimated seroprevalence of 23% was three-fold higher than the number of cases reported in the COVID-19 Integrated Surveillance data in the study area. This may be explained in part by a relatively high number of individuals presenting mild or no illness, especially those of younger age, and people who did not seek medical care or testing, but who may contribute to virus transmission in the community. 相似文献
993.
Ciccocioppo Rachele Mengoli Caterina Betti Elena Comolli Giuditta Cassaniti Irene Piralla Antonio Kruzliak Peter Caprnda Martin Pozzi Lodovica Corazza Gino Roberto Di Sabatino Antonio Baldanti Fausto 《Clinical and experimental medicine》2021,21(3):379-388
Clinical and Experimental Medicine - Human Cytomegalovirus (HCMV) and Epstein-Barr virus (EBV) are endowed with the ability of establishing lifelong latency in human hosts and reactivating in... 相似文献
994.
Allogeneic hematopoietic stem cell transplantation (alloHSCT) is a life-saving procedure used for the treatment of selected hematological malignancies, inborn errors of metabolism, and bone marrow failures. The role of neutrophils in alloHSCT has been traditionally evaluated only in the context of their ability to act as a first line of defense against infection. However, recent evidence has highlighted neutrophils as key effectors of innate and adaptive immune responses through a wide array of newly discovered functions. Accordingly, neutrophils are emerging as highly versatile cells that are able to acquire different, often opposite, functional capacities depending on the microenvironment and their differentiation status. Herein, we review the current knowledge on the multiple functions that neutrophils exhibit through the different stages of alloHSCT, from the hematopoietic stem cell (HSC) mobilization in the donor to the immunological reconstitution that occurs in the recipient following HSC infusion. We also discuss the influence exerted on neutrophils by the immunosuppressive drugs delivered in the course of alloHSCT as part of graft-versus-host disease (GVHD) prophylaxis. Finally, the potential involvement of neutrophils in alloHSCT-related complications, such as transplant-associated thrombotic microangiopathy (TA-TMA), acute and chronic GVHD, and cytomegalovirus (CMV) reactivation, is also discussed. Based on the data reviewed herein, the role played by neutrophils in alloHSCT is far greater than a simple antimicrobial role. However, much remains to be investigated in terms of the potential functions that neutrophils might exert during a highly complex procedure such as alloHSCT. 相似文献
995.
Floriana Mulas Xu Wang Shanshan Song Gopala Nishanth Wenjing Yi Anna Brunn Pia-Katharina Larsen Berend Isermann Ulrich Kalinke Antonio Barragan Michael Naumann Martina Deckert Dirk Schlüter 《Cellular & molecular immunology》2021,18(6):1512
Dendritic cells (DCs) are indispensable for defense against pathogens but may also contribute to immunopathology. Activation of DCs upon the sensing of pathogens by Toll-like receptors (TLRs) is largely mediated by pattern recognition receptor/nuclear factor-κB (NF-κB) signaling and depends on the appropriate ubiquitination of the respective signaling molecules. However, the ubiquitinating and deubiquitinating enzymes involved and their interactions are only incompletely understood. Here, we reveal that the deubiquitinase OTU domain, ubiquitin aldehyde binding 1 (OTUB1) is upregulated in DCs upon murine Toxoplasma gondii infection and lipopolysaccharide challenge. Stimulation of DCs with the TLR11/12 ligand T. gondii profilin and the TLR4 ligand lipopolysaccharide induced an increase in NF-κB activation in OTUB1-competent cells, resulting in elevated interleukin-6 (IL-6), IL-12, and tumor necrosis factor (TNF) production, which was also observed upon the specific stimulation of TLR2, TLR3, TLR7, and TLR9. Mechanistically, OTUB1 promoted NF-κB activity in DCs by K48-linked deubiquitination and stabilization of the E2-conjugating enzyme UBC13, resulting in increased K63-linked ubiquitination of IRAK1 (IL-1 receptor-associated kinase 1) and TRAF6 (TNF receptor-associated factor 6). Consequently, DC-specific deletion of OTUB1 impaired the production of cytokines, in particular IL-12, by DCs over the first 2 days of T. gondii infection, resulting in the diminished production of protective interferon-γ (IFN-γ) by natural killer cells, impaired control of parasite replication, and, finally, death from chronic T. encephalitis, all of which could be prevented by low-dose IL-12 treatment in the first 3 days of infection. In contrast, impaired OTUB1-deficient DC activation and cytokine production by OTUB1-deficient DCs protected mice from lipopolysaccharide-induced immunopathology. Collectively, these findings identify OTUB1 as a potent novel regulator of DCs during infectious and inflammatory diseases. 相似文献
996.
Isabel Legaz Jose Miguel Bolarín Elena Navarro Jose Antonio Campillo Rosa Moya María Dolores Prez-Crceles Aurelio Luna Eduardo Osuna Manuel Miras Manuel Muro Alfredo Minguela Rocio Alvarez Lpez 《Archives of Medical Science》2021,17(3):764
IntroductionThe molecular mechanisms underlying alcoholic liver fibrosis and cirrhosis are not completely understood. Hepatic fibrosis involves the interplay of diverse cells and factors, including hepatic stellate cells (HSCs), Kupffer, NK cells, and T-lymphocyte subsets. Killer-cell immunoglobulin-like receptors (KIR) are membrane receptors involved in mediation between NK and activated HSCs, regulating NK cell function through their interaction with HLA-I molecules. The aim of this study was to analyse the genetic association between KIR genes and the susceptibility to or protection from alcoholic cirrhosis (AC) in a cohort of male AC patients undergoing liver transplantation (LT) with and without concomitant viral infections.Material and methodsKIR genotyping was performed in nuclear DNA extracted from 281 AC patients and compared with 319 male controls.ResultsSignificant differences between total AC patients and healthy controls were only found in the case of KIR2DL2 and KIR2DS5. KIR2DL2 was significantly underrepresented in non-viral AC patients (52.6% vs. 63.3%; p = 0.015), while patients heterozygous for KIR2DL2 were also underrepresented in the non-viral AC group compared with controls (p = 0.034). KIR2DS5 was overrepresented in this group compared with healthy controls (p = 0.002). All these observations were only evident in AC patients older than 54 years old.ConclusionsOur data suggest a contrary effect of KIR2DL2 and KIR2DS5 in AC patients older than 54 years, in whom the presence of KIR2DL2 appears to be protective against AC, whereas the presence of KIR2DS5 seems to promote the fibrotic process, particularly in patients with no associated viral infection. 相似文献
997.
Gianfranco Mitacchione Marco Schiavone Antonio Curnis Marcello Arca Spinello Antinori Alessio Gasperetti Giosuè Mascioli Paolo Severino Federica Sabato Maria M. Caracciolo Gianmarco Arabia Laura D'Erasmo Maurizio Viecca Massimo Mancone Massimo Galli Giovanni B. Forleo 《Journal of clinical lipidology》2021,15(1):68-78
BackgroundEpidemiological evidence suggests that anti-inflammatory and immunomodulatory properties of statins may reduce the risk of infections and infection-related complications.ObjectiveWe aimed to assess the impact of prior statin use on coronavirus disease (COVID-19) severity and mortality.MethodsIn this observational multicenter study, consecutive patients hospitalized for COVID-19 were enrolled. In-hospital mortality and severity of COVID-19 assessed with National Early Warning Score (NEWS) were deemed primary and secondary outcomes, respectively. Propensity score (PS) matching was used to obtain balanced cohorts.ResultsAmong 842 patients enrolled, 179 (21%) were treated with statins before admission. Statin patients showed more comorbidities and more severe COVID-19 (NEWS 4 [IQR 2–6] vs 3 [IQR 2–5], p < 0.001). Despite having similar rates of intensive care unit admission, noninvasive ventilation, and mechanical ventilation, statin users appeared to show higher mortality rates. After balancing pre-existing relevant clinical conditions that could affect COVID-19 prognosis with PS matching, statin therapy confirmed its association with a more severe disease (NEWS ≥5 61% vs. 48%, p = 0.025) but not with in-hospital mortality (26% vs. 28%, p = 0.185). At univariate logistic regression analysis, statin use was confirmed not to be associated with mortality (OR 0.901; 95% CI: 0.537 to 1.51; p = 0.692) and to be associated with a more severe disease (NEWS≥5 OR 1.7; 95% CI 1.067–2.71; p = 0.026).ConclusionsOur results did not confirm the supposed favorable effects of statin therapy on COVID-19 outcomes. Conversely, they suggest that statin use should be considered as a proxy of underlying comorbidities, which indeed expose to increased risks of more severe COVID-19. 相似文献
998.
Antonio García‐Hermoso David Martinez‐Gomez Jorge del Rosario Fernndez‐Santos Francisco B. Ortega Jos Castro‐Piero Charles H. Hillman Oscar L. Veiga Irene Esteban‐Cornejo 《Scandinavian journal of medicine & science in sports》2021,31(1):184-192
No studies have analyzed the longitudinal associations of change in physical fitness components and obesity with academic performance. The aim of the study was to examine longitudinal associations of changes in physical fitness components and body mass index with academic performance among youth, and whether the physical fitness components are moderators of the longitudinal association between obesity and academic performance in youth. Longitudinal analyses (2 years) included 1802 youths. Physical fitness components were assessed following the ALPHA health‐related fitness test battery. Academic performance was assessed via school records. Youth in the persistently high cardiorespiratory fitness and motor ability categories (ie, fit at baseline and at 2‐year follow‐up) had higher academic performance at follow‐up than those in the persistently low category. Further, youth with normal weight at baseline and overweight/obesity at follow‐up had lower academic performance scores at follow‐up compared to those with normal weight. Also, cardiorespiratory fitness may ameliorate the negative influence of excess body mass index on academic performance at follow‐up. Promoting physical activity programs at school that include both aerobic exercise and motor tasks to improve physical fitness and reduce body mass index may not only improve physical health, but also contribute toward successful academic development. 相似文献
999.
Antonio Pallarés-Serrano Pablo Glera-Suarez Beatriz Tarazona-Alvarez María Peñarrocha-Diago Miguel Peñarrocha-Diago David Peñarrocha-Oltra 《Journal of endodontics》2021,47(3):397-403
IntroductionA study was performed of the healing rate of teeth subjected to endodontic microsurgery after a minimum follow-up of 5 years with an analysis of the influence of different pre- and postoperative factors on the outcome.MethodsThis was a retrospective study of patients subjected to endodontic microsurgery with the use of mineral trioxide aggregate (MTA) for retrograde filling between January 2011 and December 2015. In patients with multiple treated teeth, only 1 random tooth was selected for the statistical analysis. Clinical and radiographic parameters were used to assess healing. Simple binary logistic regression models were used to analyze the influence of patient age and sex, the type of tooth, prior radiographic lesion size, the presence of a post, the type of restoration, and the apical extent of prior filling of the root canal on the endodontic microsurgery success rate. Two calibrated observers evaluated the periapical radiographs on an independent basis.ResultsA total of 111 patients (63.1% women and 36.9% men) were included in the study. Of the 111 teeth analyzed, 90 were classified as healed (mean healing rate = 81.1%). Patient age and sex, the presence of a post, the type of tooth, the type of restoration, and the apical extent of prior filling of the root canal had no significant impact on the outcome. Large lesions (>5 mm) were associated with a lower healing rate than smaller lesions, although the difference was not significant. Anterior teeth had a significantly higher healing rate (93.8% maxillary and 100% mandibular) than molars (70.8% maxillary and 57.1% mandibular) (P < .05). The differences between the anterior teeth and the molars were statistically significant.ConclusionsThe mean healing rate of teeth subjected to endodontic microsurgery was 81% after 5–9 years of follow-up. The success rate was lower for upper and lower molars than for teeth in the anterior zone, although the sample was small and further studies are needed to establish whether the type of tooth influences the treatment outcome. 相似文献
1000.
Amanda Maria de Oliveira Dal Piva João Paulo Mendes Tribst Ernesto Byron Benalcázar Jalkh Lilian Costa Anami Estevam Augusto Bonfante Marco Antonio Bottino 《Dental materials》2021,37(3):e140-e150
ObjectiveDespite the increased use of monolithic crowns, their performance has yet to be determined when the minimal tooth preparation (MTP) principle is considered. The goal of this study was to evaluate the effect of MTP on the mechanical behavior, reliability and translucency of posterior monolithic ceramic crowns.MethodsDentin analogues were machined using two preparation designs (0.5 or 1 mm reduction) to receive first molar crowns in order to evaluate the monolithic crown performance. Next, 126 crowns were divided (21/g) according to the material (High translucent zirconia – YZHT, Zirconia reinforced lithium silicate – ZLS and Hybrid ceramic – HC) and thickness (0.5 or 1 mm). Tensile stress concentration was calculated using the finite element method. The crowns were adhesivelly cemented and step stress fatigued to calculate reliability for missions at 600 and 1000 N. Translucency was analyzed in 10 discs of each material and thickness.ResultsHigher stress concentration was found in thinner crowns and those with higher elastic modulus. YZHT crowns were suspended when fatigue reached 1500 N load, thus 1-parameter Weibull was used to analyze the data. Reliability was only affected by thickness at 1000 N. ZLS.5 showed lower survival than HC.5, which was similar to the groups that presented 100% survival. YZHT showed the highest strength and data scattering. ZLS1 (22.3 ± 1.4) presented higher translucency than HC1 (19.2 ± 0.6) and YZHT1 (12.0 ± 2.9), whereas ZLS.5 and HC.5 were similar to each other (26.5 ± 2.3, 26.7 ± 2.2) and superior to YZHT.5 (12.7 ± 1.2).SignificanceHC.5 combined high reliability and translucency with low stress concentration, yielding better crown performance and tooth preservation. 相似文献